Contact sports such as football result in hundreds of blows to the head in athletes each season. Traditional thought has suggested that majority of impacts have no meaningful relationship to cognitive function. Emerging research has suggested that sub-concussive impacts may result in negative changes to brain function. Ultimately, some impacts to the head will result in a concussion. Traditional management of concussions involves the clinical evaluation by a medical provider that is supported with the use of cognitive, balance, and symptom assessments. The injury diagnosis and return to play decision, however, are a subjective process. The highly variable clinical presentation of concussion makes an accurate diagnosis and return to play decision difficult. This problem is coupled with the knowledge that many of the common clinical assessments are not sensitive to post-concussion changes in performance. As such, there is a significant need for more sensitive measure of cognitive functioning. This investigation will implement a novel evaluation of electroencephalogram (EEG) recordings and standard clinical assessments in high school football athletes to evaluate concussive and sub-concussive impacts. Aim 1 will examine how pre, mid, and post-season EEG evaluations relate to the frequency and magnitude of head impacts recorded with the Head Impact Telemetry (HIT) System. Aim 2 will evaluate the relationship between post-concussion performance on EEG and standard clinical tests. The outcomes of this study will provide much needed insight into how sub-concussive impacts influence brain function and how clinical assessment tools relate to more sensitive measures of brain function. In addition, undergraduate and graduate athletic training students will have the opportunity to work on high level research and be mentored on biological research careers. PUBLIC HEALTH RELEVANCE: Commonly implemented clinical assessment tools for sport concussion may not provide the necessary sensitivity for making a safe return to play decision. A new category of impact, the sub-concussive blow, is hypothesized to result in sub-clinical changes undetectable by standard testing methodologies. Novel assessment cerebral electrophysiology may provide more information on brain networks in concussed and sub-concussed athletes. This project will support the NIH's stated mission of extending the healthy life by identifying the effect of concussive and sub-concussive blows on brain networking and their associated life- long consequences.